1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
|
# encoding: utf-8
require 'iconv'
require 'active_support/core_ext/object/blank'
require 'active_support/core_ext/string/access'
require 'active_support/core_ext/string/multibyte'
module ActiveSupport
# The Inflector transforms words from singular to plural, class names to table names, modularized class names to ones without,
# and class names to foreign keys. The default inflections for pluralization, singularization, and uncountable words are kept
# in inflections.rb.
#
# The Rails core team has stated patches for the inflections library will not be accepted
# in order to avoid breaking legacy applications which may be relying on errant inflections.
# If you discover an incorrect inflection and require it for your application, you'll need
# to correct it yourself (explained below).
module Inflector
extend self
# A singleton instance of this class is yielded by Inflector.inflections, which can then be used to specify additional
# inflection rules. Examples:
#
# ActiveSupport::Inflector.inflections do |inflect|
# inflect.plural /^(ox)$/i, '\1\2en'
# inflect.singular /^(ox)en/i, '\1'
#
# inflect.irregular 'octopus', 'octopi'
#
# inflect.uncountable "equipment"
# end
#
# New rules are added at the top. So in the example above, the irregular rule for octopus will now be the first of the
# pluralization and singularization rules that is runs. This guarantees that your rules run before any of the rules that may
# already have been loaded.
class Inflections
def self.instance
@__instance__ ||= new
end
attr_reader :plurals, :singulars, :uncountables, :humans
def initialize
@plurals, @singulars, @uncountables, @humans = [], [], [], []
end
# Specifies a new pluralization rule and its replacement. The rule can either be a string or a regular expression.
# The replacement should always be a string that may include references to the matched data from the rule.
def plural(rule, replacement)
@uncountables.delete(rule) if rule.is_a?(String)
@uncountables.delete(replacement)
@plurals.insert(0, [rule, replacement])
end
# Specifies a new singularization rule and its replacement. The rule can either be a string or a regular expression.
# The replacement should always be a string that may include references to the matched data from the rule.
def singular(rule, replacement)
@uncountables.delete(rule) if rule.is_a?(String)
@uncountables.delete(replacement)
@singulars.insert(0, [rule, replacement])
end
# Specifies a new irregular that applies to both pluralization and singularization at the same time. This can only be used
# for strings, not regular expressions. You simply pass the irregular in singular and plural form.
#
# Examples:
# irregular 'octopus', 'octopi'
# irregular 'person', 'people'
def irregular(singular, plural)
@uncountables.delete(singular)
@uncountables.delete(plural)
if singular[0,1].upcase == plural[0,1].upcase
plural(Regexp.new("(#{singular[0,1]})#{singular[1..-1]}$", "i"), '\1' + plural[1..-1])
singular(Regexp.new("(#{plural[0,1]})#{plural[1..-1]}$", "i"), '\1' + singular[1..-1])
else
plural(Regexp.new("#{singular[0,1].upcase}(?i)#{singular[1..-1]}$"), plural[0,1].upcase + plural[1..-1])
plural(Regexp.new("#{singular[0,1].downcase}(?i)#{singular[1..-1]}$"), plural[0,1].downcase + plural[1..-1])
singular(Regexp.new("#{plural[0,1].upcase}(?i)#{plural[1..-1]}$"), singular[0,1].upcase + singular[1..-1])
singular(Regexp.new("#{plural[0,1].downcase}(?i)#{plural[1..-1]}$"), singular[0,1].downcase + singular[1..-1])
end
end
# Add uncountable words that shouldn't be attempted inflected.
#
# Examples:
# uncountable "money"
# uncountable "money", "information"
# uncountable %w( money information rice )
def uncountable(*words)
(@uncountables << words).flatten!
end
# Specifies a humanized form of a string by a regular expression rule or by a string mapping.
# When using a regular expression based replacement, the normal humanize formatting is called after the replacement.
# When a string is used, the human form should be specified as desired (example: 'The name', not 'the_name')
#
# Examples:
# human /_cnt$/i, '\1_count'
# human "legacy_col_person_name", "Name"
def human(rule, replacement)
@humans.insert(0, [rule, replacement])
end
# Clears the loaded inflections within a given scope (default is <tt>:all</tt>).
# Give the scope as a symbol of the inflection type, the options are: <tt>:plurals</tt>,
# <tt>:singulars</tt>, <tt>:uncountables</tt>, <tt>:humans</tt>.
#
# Examples:
# clear :all
# clear :plurals
def clear(scope = :all)
case scope
when :all
@plurals, @singulars, @uncountables = [], [], []
else
instance_variable_set "@#{scope}", []
end
end
end
# Yields a singleton instance of Inflector::Inflections so you can specify additional
# inflector rules.
#
# Example:
# ActiveSupport::Inflector.inflections do |inflect|
# inflect.uncountable "rails"
# end
def inflections
if block_given?
yield Inflections.instance
else
Inflections.instance
end
end
# Returns the plural form of the word in the string.
#
# Examples:
# "post".pluralize # => "posts"
# "octopus".pluralize # => "octopi"
# "sheep".pluralize # => "sheep"
# "words".pluralize # => "words"
# "CamelOctopus".pluralize # => "CamelOctopi"
def pluralize(word)
result = word.to_s.dup
if word.empty? || inflections.uncountables.include?(result.downcase)
result
else
inflections.plurals.each { |(rule, replacement)| break if result.gsub!(rule, replacement) }
result
end
end
# The reverse of +pluralize+, returns the singular form of a word in a string.
#
# Examples:
# "posts".singularize # => "post"
# "octopi".singularize # => "octopus"
# "sheep".singularize # => "sheep"
# "word".singularize # => "word"
# "CamelOctopi".singularize # => "CamelOctopus"
def singularize(word)
result = word.to_s.dup
if inflections.uncountables.include?(result.downcase)
result
else
inflections.singulars.each { |(rule, replacement)| break if result.gsub!(rule, replacement) }
result
end
end
# By default, +camelize+ converts strings to UpperCamelCase. If the argument to +camelize+
# is set to <tt>:lower</tt> then +camelize+ produces lowerCamelCase.
#
# +camelize+ will also convert '/' to '::' which is useful for converting paths to namespaces.
#
# Examples:
# "active_record".camelize # => "ActiveRecord"
# "active_record".camelize(:lower) # => "activeRecord"
# "active_record/errors".camelize # => "ActiveRecord::Errors"
# "active_record/errors".camelize(:lower) # => "activeRecord::Errors"
def camelize(lower_case_and_underscored_word, first_letter_in_uppercase = true)
if first_letter_in_uppercase
lower_case_and_underscored_word.to_s.gsub(/\/(.?)/) { "::#{$1.upcase}" }.gsub(/(?:^|_)(.)/) { $1.upcase }
else
lower_case_and_underscored_word.first.downcase + camelize(lower_case_and_underscored_word)[1..-1]
end
end
# Capitalizes all the words and replaces some characters in the string to create
# a nicer looking title. +titleize+ is meant for creating pretty output. It is not
# used in the Rails internals.
#
# +titleize+ is also aliased as as +titlecase+.
#
# Examples:
# "man from the boondocks".titleize # => "Man From The Boondocks"
# "x-men: the last stand".titleize # => "X Men: The Last Stand"
def titleize(word)
humanize(underscore(word)).gsub(/\b('?[a-z])/) { $1.capitalize }
end
# The reverse of +camelize+. Makes an underscored, lowercase form from the expression in the string.
#
# Changes '::' to '/' to convert namespaces to paths.
#
# Examples:
# "ActiveRecord".underscore # => "active_record"
# "ActiveRecord::Errors".underscore # => active_record/errors
def underscore(camel_cased_word)
camel_cased_word.to_s.gsub(/::/, '/').
gsub(/([A-Z]+)([A-Z][a-z])/,'\1_\2').
gsub(/([a-z\d])([A-Z])/,'\1_\2').
tr("-", "_").
downcase
end
# Replaces underscores with dashes in the string.
#
# Example:
# "puni_puni" # => "puni-puni"
def dasherize(underscored_word)
underscored_word.gsub(/_/, '-')
end
# Capitalizes the first word and turns underscores into spaces and strips a
# trailing "_id", if any. Like +titleize+, this is meant for creating pretty output.
#
# Examples:
# "employee_salary" # => "Employee salary"
# "author_id" # => "Author"
def humanize(lower_case_and_underscored_word)
result = lower_case_and_underscored_word.to_s.dup
inflections.humans.each { |(rule, replacement)| break if result.gsub!(rule, replacement) }
result.gsub(/_id$/, "").gsub(/_/, " ").capitalize
end
# Removes the module part from the expression in the string.
#
# Examples:
# "ActiveRecord::CoreExtensions::String::Inflections".demodulize # => "Inflections"
# "Inflections".demodulize # => "Inflections"
def demodulize(class_name_in_module)
class_name_in_module.to_s.gsub(/^.*::/, '')
end
# Replaces special characters in a string so that it may be used as part of a 'pretty' URL.
#
# ==== Examples
#
# class Person
# def to_param
# "#{id}-#{name.parameterize}"
# end
# end
#
# @person = Person.find(1)
# # => #<Person id: 1, name: "Donald E. Knuth">
#
# <%= link_to(@person.name, person_path(@person)) %>
# # => <a href="/person/1-donald-e-knuth">Donald E. Knuth</a>
def parameterize(string, sep = '-')
# replace accented chars with their ascii equivalents
parameterized_string = transliterate(string)
# Turn unwanted chars into the separator
parameterized_string.gsub!(/[^a-z0-9\-_\+]+/i, sep)
unless sep.blank?
re_sep = Regexp.escape(sep)
# No more than one of the separator in a row.
parameterized_string.gsub!(/#{re_sep}{2,}/, sep)
# Remove leading/trailing separator.
parameterized_string.gsub!(/^#{re_sep}|#{re_sep}$/i, '')
end
parameterized_string.downcase
end
# Replaces accented characters with their ascii equivalents.
def transliterate(string)
Iconv.iconv('ascii//ignore//translit', 'utf-8', string).to_s
end
if RUBY_VERSION >= '1.9'
undef_method :transliterate
def transliterate(string)
warn "Ruby 1.9 doesn't support Unicode normalization yet"
string.dup
end
# The iconv transliteration code doesn't function correctly
# on some platforms, but it's very fast where it does function.
elsif "foo" != (Inflector.transliterate("föö") rescue nil)
undef_method :transliterate
def transliterate(string)
string.mb_chars.normalize(:kd). # Decompose accented characters
gsub(/[^\x00-\x7F]+/, '') # Remove anything non-ASCII entirely (e.g. diacritics).
end
end
# Create the name of a table like Rails does for models to table names. This method
# uses the +pluralize+ method on the last word in the string.
#
# Examples
# "RawScaledScorer".tableize # => "raw_scaled_scorers"
# "egg_and_ham".tableize # => "egg_and_hams"
# "fancyCategory".tableize # => "fancy_categories"
def tableize(class_name)
pluralize(underscore(class_name))
end
# Create a class name from a plural table name like Rails does for table names to models.
# Note that this returns a string and not a Class. (To convert to an actual class
# follow +classify+ with +constantize+.)
#
# Examples:
# "egg_and_hams".classify # => "EggAndHam"
# "posts".classify # => "Post"
#
# Singular names are not handled correctly:
# "business".classify # => "Busines"
def classify(table_name)
# strip out any leading schema name
camelize(singularize(table_name.to_s.sub(/.*\./, '')))
end
# Creates a foreign key name from a class name.
# +separate_class_name_and_id_with_underscore+ sets whether
# the method should put '_' between the name and 'id'.
#
# Examples:
# "Message".foreign_key # => "message_id"
# "Message".foreign_key(false) # => "messageid"
# "Admin::Post".foreign_key # => "post_id"
def foreign_key(class_name, separate_class_name_and_id_with_underscore = true)
underscore(demodulize(class_name)) + (separate_class_name_and_id_with_underscore ? "_id" : "id")
end
# Ruby 1.9 introduces an inherit argument for Module#const_get and
# #const_defined? and changes their default behavior.
if Module.method(:const_get).arity == 1
# Tries to find a constant with the name specified in the argument string:
#
# "Module".constantize # => Module
# "Test::Unit".constantize # => Test::Unit
#
# The name is assumed to be the one of a top-level constant, no matter whether
# it starts with "::" or not. No lexical context is taken into account:
#
# C = 'outside'
# module M
# C = 'inside'
# C # => 'inside'
# "C".constantize # => 'outside', same as ::C
# end
#
# NameError is raised when the name is not in CamelCase or the constant is
# unknown.
def constantize(camel_cased_word)
names = camel_cased_word.split('::')
names.shift if names.empty? || names.first.empty?
constant = Object
names.each do |name|
constant = constant.const_defined?(name) ? constant.const_get(name) : constant.const_missing(name)
end
constant
end
else
def constantize(camel_cased_word) #:nodoc:
names = camel_cased_word.split('::')
names.shift if names.empty? || names.first.empty?
constant = Object
names.each do |name|
constant = constant.const_get(name, false) || constant.const_missing(name)
end
constant
end
end
# Turns a number into an ordinal string used to denote the position in an
# ordered sequence such as 1st, 2nd, 3rd, 4th.
#
# Examples:
# ordinalize(1) # => "1st"
# ordinalize(2) # => "2nd"
# ordinalize(1002) # => "1002nd"
# ordinalize(1003) # => "1003rd"
def ordinalize(number)
if (11..13).include?(number.to_i % 100)
"#{number}th"
else
case number.to_i % 10
when 1; "#{number}st"
when 2; "#{number}nd"
when 3; "#{number}rd"
else "#{number}th"
end
end
end
end
end
# in case active_support/inflector is required without the rest of active_support
require 'active_support/inflections'
require 'active_support/core_ext/string/inflections'
|